Strain-releasing mechanism



Mar. 20, 1923.

A. PESTEL.

STRAIN RELEASING MECHANISM.

4 SHEETS-SHEET 1.

FILED MAY 21,1920.

FIG.)

FIQS

m qmlllllllllllllllfllllll INVENTOR Maw A. PESTEL.

STRAIN RELEASING MECHANiSM.

4 SHEET SHEET 2 FILED MAY 2h1920.

FIGJZ zozzimw FHGJB INVENTOR /a W FIGJT Mar. 20, 1923.,

. A. PESTEL.

STRAIN RELEASING MECHANISM.

4 SHEETS-SHEET 4.

FILED MAY 21, 1920- FIG. 2.5

17!: l 78 M8 3W INVENTOR- it a ARTHUR, PESTEL, OF NEH/V YORK, N. Y.

STRAIN-RELEASING MECHANISM.

Application filed May 21,

To all 207mm it may concern:

Be known that l, finrnnnl i 111., a citizen of the United States, residing at Few York, county and State of New York, have invented certain new and useful Improve ments in Strain-Releasing Mechanism. of which the following is a full, clear, and exact specification.

This invention relates to improvements in mechanism for releasing strains and is applicable to trifle-rent forms of mechanism in which release of excessive strains on machine elements is desired.

The object of my invention is to provide mechanism which will eliminate the breating of taps, drills and other work-performing elements and whereby a device is introduced between power transmitting" members. which device will give way whenever the strain on said members does become eX- cessive.

Heretot'ore it has been customary to provide strain releasing mechanism with drilling; and tapping machines or attachments. which mechanism were built into the chine or attachment, and in order to obtain greater or lesser strain-resistance, applicable for larger or smaller sized taps drills respectively, the operator had to accurately adjust said strain releasing; lilQCllzlnism, which involved more or less mechanical skill and an unnecessary waste of time.

The object of my invention is to provide separate strain releasing); units attachable to drilling or tapping machines or the like.

Each unit is made or adjusted. to withstand a certain definite strain only and it may be interchanged for other units ha a strain resistance of either greater or les degrees. My invention is adaptable to d if ferent machines and apparatus and can be used in connection with clutches. couplii and the like, but I desire to especially apply the same in connection with tapping and drilling machines.

in carrying out the invention, 1 also utilize the break-pin shown and descril ed in U. S. Patent Application Ser. No. 3437, 190, filed February 9th 1920, to which reterence may be had.

In the accompanying drawings:--Figs. 1, 2, 3, #l, and 6 show views of tapnolder. such as are used on screw machines and turret lathes and of which 1 is a front view. Fig. 2 a side view the line 2----f.% Fig. 7., Fig. a plan view on the line 3-3 Serial N0. 383,032.

Fig. 1, Fig. 4 a plan view and Figs. 5 and 6 a detailed plan view and rear view respectively oi the breakcollar with the chuck shown in dotted lines, to make the views clearer. Fig. 7 is a view of a brealqdin.

ri -S. s, 9, 10, 11, 12, 13, 14. and 15 SllOW views 01'. an other tapholder for screw machines and turret lathes, but of a design dilierent from that shown in Figs. 1, 2, 3, 4. 5 and 6.

Fig. 8 shows a sectional side view of the assembled shank and chuck of said tap holder, Fig. 9 is a front view on the line 9 9 Fig. 8. Fig. 10 is a front view of a strain releasing; unit attachable to said shank and chuck Fig. 8; Fig. 11 is a side view on the line ll ll Fig. 10; Fig. 12 is plan view on the line 12-12 Fig. 10; Fig. is partial bottom view of Fig. 11; Fig. a detailed modified view of a spring :hment. Fig. 15 is a plan View of the niplete tapholder assembled. Fig. 16 is side view of a wrench and Fig. 17 is a ectional plan view of same on the line 7-1? Fig. 16.

Figs. 18, 19, 20, 21, 22, 23 and 24E show views of a strain-releasing unit to be used in connection with high speed drilling attachments, tapping machines and the like.

Fig. 18 is a plan view of said unit on the line 18-18 a 19. 19 is a sectional view on the line 19-19 Fig. 18 and Fig. 20 a sectional view on the line 20-20 Fig. 1.8.

Fig. 21 shows a sectional view of it high speed drilling attachment connected with said strain releasing unit. Fig. 22 shows a plan view of a plate; Fig. 23 a sectional view of same on the line 23-23 F ig. 22. Fig. is a partial view of a. cylinder.

Figs. 25, 26, 27, 28 and 29 show views of a chuckholder for drillpresses, lathes and similar machines.

Fig 25 shows a sectional side view of the collet and head of said chuckholder. F in. 26 is a tront view of a strain releasing unit, attachable to said collet and chuck, F ig. 25.

Fig. 27 is a side view on the line 2727, Fig. 26. 28 is a rear view of said unit. Fig. 29 is plan view or" the complete chuckholder assembled.

Referring to Figs. 1, 2, 3, i, 5, 6 and 7 No. 1 indicates a shank, made to it into the l'iead oi the turret ot a screw-machine and to he clamped thereto in any well known manner.

Casing 2, which is fitted to the rim 8 of shank 1 is fastened to said rim with three screws 4 and one longer screw 5. The breakcollar 7, which is rotatable in and between said shank rim 3 and casing 2 on annular bearing surfaces 8 and 9 respectively, has adjacent and concentric to each of said bearing surfaces a breakrim 10 and 11 respectively.

Said breakrims, which are larger in diameter than said bearing surfaces, are cut open on one place at a slight angle as shown on ends 12 and 13, Figs. 3 and 6 and relieved opposite each end approximately one fourth of the circumference of said breakrims as shown at 14 and 15 Fig. 6. y

The head or chuck. 16, holding a tap 17 by means of two semicircular clampblocks 18, 19 and a screw 20, has a shank 21 which is concentrically and rotatably mounted in breakcollar 7. Said shank, which has a hole 22, has also at its furthest end a groove 23 into which is fitted a fiat pin 24, fastened to said shank by means of a rivet or screw 25.

Said pin has on one end an extension 26, long enough to clear a shallow hole 27 in breakcollar 7. Said hole has a depth alike to the thickness of pin 24 at one third the circumference of said hole and the depth alike to the double thickness of pin 24 at the remainder of the circumference.

One step 28, Fig. 5, obtained by means of these different depths is cut at approximately right angle, to allow extension 26 to firmly rest against said step, while the other step 29 is formed on a slant and gradually rises from the lower to the upper surface of hole 27. Bearing surface 3 of breakcollar 7 has two clutch teeth 30 and 31 Figs. 5 and 6 respectively, to engage pins 32, fast in head 16.

Casing 2 has on its circumference a rectangular opening 33 in which are held by means of two screws 5 and 6 two steel guide plates 34. These plates, both of which are alike, have in the middle a triangular groove 35 which is relieved at 36.

When the plates are assembled, grooves 35 will form a rectangular opening, large enough to allow breakpin 37 to pass freely. Breakpin 37, which may be made of any suitable material, has on both sides a row of definitely spaced notches 38, thusdividingsaid breakpin into a row of links 39.

The length of each link is approximately alike to the height of ends 12 and 13 of breakrims 10 and 11 respectively.

A snappin 40, movable in an extension 41 of casing 2, pressed towards the centre by means of a spring 43, has fast on its other end a knob 44 and engages with its other larger end 45 one of the lowest notches 38 of pin 37 thus preventing said pin from coming out. Casing 2 has an opening or outlet 46 which has the approximate width of breakpin 37 and serves the purpose to permit the discharge of a broken link.39.

Breakpin 47 Fig. 7, which is a modified view of pin 37, has links 48 formed by slots 49 which at the bottom are V shaped, so as to insure the breaking of said links at this particular point. It is of course understood that the depths of said slot-s depend on the size of the work performing element, as tap 17. g

The operation of said tapholder is as follows: The tapholder which is fastened in the turret head of a screw machine is fed against the work rotating in a chuck of' said machine, forcing the tap 17 and head 16 against the breakcollar 7, thus allowing pins 32 to engage the clutch teeth 30 and 31, forcing the breakcollar 7 to rotate in a clockwise direction.

Breakpin 37, held stationary; in guide plates 34 and positively engaging breakcollar 7 at the rim ends 12 and 13, prevents said collar from turning, but will yield and break, should the strain on the tap be near its breaking point. 39 thus broken off, will be carried along with the now disengaged breakcollar, until .it reaches the opening 46, where it will drop out and allow the breakcollar and therefore the tap 17 to rotate with the work untilthe 5 machine has been stopped.

in order to again lock said breakcollar,

the operator will draw back snappin 40 by means of knob 44 and push in the breakpin until its lower link has again positively engaged the rim-ends 12 and 13 as indicated in Figs. 2 and 3. If however the link has not been broken and the tap has threaded the work its full depth, the rotation of thechuck in the screw-machine is reversed, the turrethead and therefore the tapholder and tap is drawn back. This will disengage pins 32 and bring in engagement extension 26 of pin 24, with. the step 28, thus exerting a rotary anticlockwise movement to said breakcol Thestrain in this case is taken up by the rim end 13 which will force link 39 to lar.

yield and break should the strain be near the breaking point of the tap.

It will be noticed, that the breakcollar 7 exerts torsional strains to the breakpin 37, which strains force the link 39 to perform a quasi rotary movement. before breaking.

It is of course understood, that this tapholder may also be'fas-tened to the chuck In such a case the link 4 with a groove 101 into which fits shoulder screw 50, held in extension 98, preventing said sleeve from moving in and out of said hole. At each end of sleeve 100 are clutch teeth 51 and 52 for engagement of either pins 53 in head or chuck 54; or pin 55 fast in shank 56 rotatable in sleeve'lOO.

The strain r leasing unit 206 Figs. 10, 11 and 12 has a sleeve 57 with a large inner h le to slide over extension 98 Fi 8. *7 or said sleeve has three extensions i -shaped grooves or friction races (ii in which are resting three posts 62 "fast casing c2; each or said posts having two angular friction faces 20?. Casing 63 is slidable and rotatable on sleeve 57' and extensions e0. Said casing and therefore posts (53 are drawn against extensions by means of three sprins 's or pressure elements at held to i--i 59 my means 01 pins 65 passing hole (36 and to casing 63 by means of wire ring (57 resting in groove 68. The looped end (39 oi? each spring Gel passes 'ough clearance hole 86, Fig. 11.

.Fihould it be desirable to make said sprin s 6% adjustable, adjustment screws 70, l 1e w' checlrnuts 71 may be substituted for wire ring 67, in which case the looped ends 69 of springs ca would be held in holes 72 at the end of each screw 70.

in the center of casing 63 is a hole .73

Fig, 10, with two tongues T l and rectangular shaped opening 75, large enough to admit and positively engage pin 76, fast on sleeve 100, Figs. 8 and 9.

The distance between the extreme end of pin and the center of sleeve 100 is slightly more than the length of the radius of hole ncasing 63, in order to force the operator to properly locate pin or engaging element 76 in opening when assembling unit 206 with shank and chuck 77.

The head 78 of shoulder screw 79, and 1?; in extension 60 of sleeve 57 passes 'ough casing (5%, which casing at this pl ce has a slot 80. serving the purpose to prevent the same to he turned too rar to ier the rightor left. or to be drawn out, h in these cases might stretch the springs unnecessarily and change the torn sions of same. Y

The three threaded holes 81 in extensions 9 are for the purpose of locking unit 206 to rim 97 by means oi? screws 82 Fig.8. fdaid screws have a shoulder 83 and fast to the ends of shanks 8 1 knurled knobs 85 to presaid screws from falling out. when the shank and chuck T7 and strain releasing unit 206 Min. 15 are assembled the tion of said tanholdcr similar to the older shown in Figs. 1. 2, 3, 4. 5 and 6 i. the difference that if the strain on tap is too great. pin 76 which imparts a strain 63, will force pos s 62 out oi: i1" positions and turn until they have -rhed the edges of extensions 60;. when springs 6 1 will draw casing 63 towards sleeve 5'? and thus positively disengage pin 7 from casing 63., allowing sleeve 100 and therefore chuck 54: and tap 87 to rotate freel The'end of extension 98 is partly relieved at 88, the depth of said relieve being a little more than the thickness 01'' the tongues 74 on casing 63 Fig. 10 and serves the purpose to allow said tongues suflicient clearance when casing 63 is in a released position.

To return said casing to an engaged posiiion. it is necessary to partly turn the same and draw it forward until posts 63 have i-in. engaged grooves 61. In some cases the power required to return the casing may necessitate a 'rench 89 Figs. 15 and 17. This wrench has on one end a pinhandle 90 and or; the other a guide pin 91 which fits in hole Figs. 8 and 9.

The recess 93 in rim 97 is made large gh to allow tongue 9% of wrench 89 ireely pass into same, so that wrench tongue may engage in notch Fig. 15

l hy turning said wrench replace casing o an engaged position.

of course understooch that in order as provide strain releasing units of greater or lesser tensions either stronger or weaker *lo 102 indicates a sleeve with a threaded or 103, a rim 10 1 and two tongues 105 grooves 106 at their ends. Resting in o ves and fastened to said tongues by means of two screws is a plate 107 Figs. 22 and 23 which has in its center a threaded hole 108 and at each end a screw hole 157. Eyescrew 109 held in plate 107 and locked thereto by means of nut 110, has on one end a slot 111 and on the other an eye or hook 1112. holding therein looped end 113 of spring or pressure element- 11 1. Cylinder 115 movable in hole 116 of sleeve 102 has resting on recess 11'? a washer 118 Fig. 20. llotatahle in the cupshaped hole 119 of said washer a semihall 120 with a hole 121 and a slot 122 in which rests flattened out end 12., of spring 114.

Rina on cv inder 115 has on its lower end a clutch-face 125.. on the other end a shoulder and is partly covered by hole 127 in sleeve 102. The upper end oi eylinder 115 has two notches 128 Fig. 24.. arranged opposite to other and adjacent thereto two other notches 129.. having each a frictionface 208.. said notches are however more shallow than not hes 128. Resting on said frictioniiaces 298 are two angular shaped extensions 13-0 19 and 2-? forming part of plate 10? having each :1 friction fire 209 and are drawn against the cylinder ill "a is as follows:

by. means of spring 114. Said extensions are inade eircular on their outer edges 131 Fig.22, so as to fit into hole 116.

Casing 132 has on the inside of its shell 133 two tongues 134 the inner ends' 135 snugly fitting on cylinder 115.

Two screws-136, with their heads sunk into shell 133, connect and hold together casing 132 and cylinder 115.

Rim' 104 has a number of holes 137.

In Fig. 21, which indicates plan view of a high speed drilling attachment, cover 138 which is fastened to casing 139 in any well known manner, has rotatable therein a driving shaft 140 and fast to same a large gear 141, driving a smaller gear 142 rotatable in bearing 143. Shoulder 144 of gear 142 has on the inside athread 145 into which is screwed a strain releasing unit 146 as shown on a larger scale in Figs. 18, 19, 20, 22, 23 and 24. Clutchface 125 of said unit engages a'clutchface or engaging element 148 of clutch member 147 which has a threaded extension 149 screwed into a hollow spindle 150.

Said spindle is rotatable in gear 142 on one end and in casing 139 on the other and has fast to it a large gear 151 which drives a smaller gear 152 fast on chuck spindle 153 which in turn is rotatable in a loose bushing 154 in shaft 140 on one end and in casing 139 on the other. Fast to spindle 153 and only partly shown is a chuck 155.

The operation of said strain releasing unit The high speed drilling attachment is fastened in the spindle of a drill press, lathe or other suitable machine by means of the driving shaft 140, driving the chuck spindle 153 at a higher speed than that of shaft 140 onaccount of the different ratio of gears 141, 142, 151 and 152.

Should the strain on a tool fastened in nhuck 155 become too great, the hollow spindle and its clutch member 147 which '1' imparts a strain on cylinder 115 Figs. 19

and 20 will eventually force said cylinder to retard its motion until extensions 130 on plate 107 have reached the edges of frictionfaces 208 and 209, when spring 114 will draw up said cyhnder and force extensions 130 to engage notches 128, thus positively disengagingthe two clutch faces 125 and 148 Fig. 21 and stop hollow spindle 150, gears 151 and 152 and chuck with its tool from rotating.

To return the cylinder from a positively disengaged to an engaged position, the operator stops the machine and pushes down and partly rotates casing 132 until frictionfaces 209 have again engaged frictionface's 208.

To fasten or unscrew said unit to said attachment a pin or pinwrench may be inserted in one of the holes 137 of rim 102 and turned in the direction desired. I

In order to provide strain releasing units of greater or lesser tension, either the springs may be: varied or the angles of frictionfaces 208 and 209 may befchanged. I

It is of course understood that this unit may also be applied on tapping attachments similar to the one shown in my United States Patent No. 1,410,717, issued h larch 28, 1922.

leferring to Figs. 25, 26, 27,1 and 29, Fig. 25 indicates a colletand chuck 158 of a chuckholder 159 Fig. 29, having a tapered shank 160 made to fit into the spindle of any standard drillpress, milling machine and the like. I

Rotatable in hole 161 of said shank is a chuck spindle 162, having fast to its larger end 163 a chuck 164 with a drill 165. The other end 166 of said spindle is rounded and abuts against a steel disk 167 which serves the purpose to take up the thrust imparted from the chuck to saidspindle.

Protruding into a groove 168 of spindle 162 is a snap pin 169 with a shoulder 170 to prevent said 'pin from resting on the bottom of groove 168'. This snap pin which is guided in hole 171 of rim 172 is pressed in the direction ofv chuck-spindle 162 by means of a spiral spring 173. At the other end of said spring in hole 171 is a screw 174 which has a slot 175. Fast to shank 176 of pin 169 is a small late 177 which has the same width as slot 11 8 in rim 172.

Near the longer end of said plate in. rim 172 is a small notch 179, which serves the purpose to enable the operator to easily grasp plate 177, lift the snap pin and take out chuck spindle 162. i

Riveted to rim 172 are two lock pins 180 Fig. 29 with a head 181, small enough to clear holes 182 in threaded sleeve 183 Figs. 27 and 28. To concentric slots 184, 185 have the approximate width of the diameter of pins 180 at-the outer surface 186 of said sleeve and an approximate depth of the length of the protruding pins 180. 'Further back however said slots have the same width as the diameter of holes 182.

Rotatable in sleeve 183 and pressed against shoulder 187 by means of shoulder 188 of adjustment ring 189, is a friction'ring which has a slot 191. Lockring 192 serves the purpose to lock adjustment ring 189 after the desired pressure on'friction ring 190 has been obtained. 4

Rings 189 and 192 are knurled on their circumferences 193 and have each a number of holes 194 to securely lock said rings with a pin or pin Wrench. 1

Hole 195 of sleeve 183 fits shoulder 196,

and the unit 197 may be slipped over chuck 199 of friction ring 190. A similar rectangular opening 200 in threaded sleeve 183 serves as a clearance hole to allow pin 198 to pass .aid sleeve when attaching the unit.

in some cases chuck 16 1- may be larger in diameter than hole 195 in sleeve 183. The operator will then remove chuck and spindle from collet 158 in the way already lescribed, slip on the desied unit and again insert said chuck and spindle.

In operation the chuck spindle 162 and "are chuck is turned by means 01" i l'iCtiOD ring 190. lit the strain on drill 165 is near the breaking point of said drill, triction in 190 will yield and turn with chuck spinifllc until the strain has een released from the drill or the machine has been stopped.

it will be noted, that in each one of the various constructions as shown and described, are employed members and elements performing like tunctions. These members and elements are listed below under separate head 1's, designating their functions. The names of those headings will be employed in claims to follow. mrain inducing members: .Fi s. 1 to 7 guide plates 34-; Figs. 8 and 9 rim 9? with screws Fig. 21 gear 1-l-2; 2 3 and 29 rim 172 with lock pins 180.

. ain rel Basing unit or units:

7 breakpins 37 and 47 respectively; 11 and 12 unit 206; Fig. 21 unit EG, n ms. 26, 27 and 28 unit 197.

Strain receiving members: Fig. 3 complete head 16 with tap 17 8 complete head 5-iwith tap 8'? Fig. 1 clutch member 1 17; Fig. 25 spindle 162.

F train transmitting elements: Figs. 2 and 'i the second. engaged link of units 37 and 17 respectively, it the complete tap holder is rotate-s i" 10 i1 and 12 sleeve 57 of unit Figs. 19 and 20 sleeve 102 of unit 146,

. 27 and 28 sleeve of unit 197.

. g ase elements: Tlie lower link. of units .31 and l? of 2 and '7 respectively, it the complete tap holder is rotated; 10, i and 12 casing of unit 206; Figs. 19 1nd 2 2; cylinder 115; 27 friction ring Lit o't unit 197.

ivingthus described my invention, it is oi. course understood, that the strain releasing unit 206 Fig. 15 may be used in connection with the collet and chuck shown in Fig. 25 and that unit 197 26, 27, 28 may be made to be used in connection with shank and chuck "7 Fig. 8.

it is also understood that i do not hold m sclt to the precise construction of these mechanisms and that 1 consider myself at liberty to vary the arrangements and constructions of same without departing from the spirit of my invention.

I claim:

in mech anism o? the character described, a strain inducing member, a unit, a strain forming a permanent part of said inducing member, receiving member, a strain transmitting and a release element in said unit, spring means connecting both said elements and means to positively engage said unit with said inducing and said receiving member.

2. In mechanism of the character described, a strain inducing member, a unit, a. strain receiving member, a strain trans- .iitting and a release element in said unit. spring means connecting both said elements and means to attach and detach said unit to and from one of said members for positive engagement with the other of said members,

without dislocating either of said members.

3. In mechanism of the character described, a rotatable strain inducing member, a unit, a rotatable strain receiving member, a strain transmitting and a release element in said unit, spring means connecting both said elements and means to attach and detach said unit to and from one of said members for positive engagement with the other of said members, without dislocating either of said members.

t. In mechanism of the character described, a strain inducing member. a unit, a strain receiving member rotatable in said inducing member "forming a permanent part of the latter, means to positively ensaid unit with said inducing and said receiving members, elements forming part of said unit to transmit a strain or strains from said inducing member to said receiving member and means to repeatedlv set free said strains in said unit.

5. In mechanism of the scribed, a strain inducing member, a uni a strain receiv (Y member rotatable in r inducing men s to attach and dctach said unit to and from one of said mem bers 't'or positive engagement with the other or said members, without dislocating either of said members, said unit to transmit a strain or strains 'ti'oin said inducing memher to said receiving u'ien'iber and means to repeatedly set free said strains in said unit.

6. In mechanism of the character described, a strain inducing member, a unit, a strain receiving member rotatable in said. inducing member forming a permanent part or the latter, means to positively engage said unit with said inducing and receiving members, elements forming part of said unit to transmit a strain or strains from said inducing member to said receiving member and a release element in said unit to repeatedly set :tree said strains in said unit.

7. In a mechanism of the character described, a strain inducing member, a unit, a

L l, character ucstrain receiving member rotatable in said in- 'for positive engagement with the other of said receiving member and a releaseelement in said unit, to repeatedly set free said strains in said unit.

8. In mechanism oi the character described, a strain inducing member, a unitia strain receiving member rotatable in said inducing member forming a permanent part of the latter, means to positively engage said unitwith said inducing and said receiving members, elements forming part of said unit'to transmit strains from said inducing member to said receiving member in two different directions and means to repeatedly set free said strainsv in said unit.

9. In mechanism of the character described, a strain inducing member, a unit, a strain receiving men'iber rotatable in said inducing member forming a permanent part of the latter, means to positively engage said unit with said inducing and said. receiving members, elements forming part oi said unit to transmit strains from said inducing member to said receiving member in two different directions and a release element in said unit to repeatedly set "free said strains in said unit. i i V 10. In mechanism of the character described, a strain inducing member, a unit, a strain receiving member forming a permanent part of said inducing member, means to positively engage said unit With said members,' to transmit a strain or strains from said inducing member to. said receiving member and further means to repeatedly set free said strains in said unit.

11. In mechanism of the character described, a strain inducing member, aunit, a strain receiving member forming a permanent part of said inducing member, means to positively engage said unit with said members, to transmit a torsional strain or strains from said inducing member to said receiving member and further means to repeatedly set free said strains in said unit.

12. In mechanism of the character described, a strain inducing member, a unit, a strain receiving member forming a permanent part of said inducing member, means to positively engage said unit with said men'ibers, to transmit strains in tWO diiierent directions from said inducing member to said receiving member and further means to repeatedly set free said strains un1t.

13. In mechanism of the character de scribed, a strain inducing member, a unit, a strain receiving member forming a permanent part of said inducing member, means to positively engage said unit with said members, to transmit a strain or strains in said from said inducing member to said receiving member and. a release element in said unit, to repeatedly set free said strains in said unit.

li. In mechanism oi the character described, a-strain inducing member, a unit,

other of said members, Without dislocating o either of said members, said unit to trans mit strain er strains from said inducing member to said receiving member and fun ther strains in said unit.

16. In mechanism of the character described, a strain inducing member, a unit, a strain receiving member, means to attach and detach said unit to and from one of said members for positive engagement with the other of said members, without dislocating either of said members, said unit to transmit a strain. or strains from said in ducing membe to said receiving member and yielding to said strains in said unit.

17. In mechanism of the character described, astrain inducing member, a unit, strain receiving member, means to attach and detach said unit to and from one of said members for positive engagement with i the other of said members, Without dislo eating either of said members, said unit to transmit strains in two different directions from said inducing member to said receiving' member and torepeatedly set free said strains in said unit.

18. In mechanism of the character described, a strain inducing member, a unit, a strain receiving member, means to attach and detach said unit to and from onset said members for positive engagement with the other of said members, Without disloeating either of said members. said unit to transmit a strain or strains from said inducing member to said receiving member and a release element in said unit, to repeatedly set free said strains in said unit.

19. In mechanism of the character described, a strain inducing member, a round strain transmitting element, a plurality of extensions on said element, each of; said extensions having one or more angular frictionitaces, the total length of said frictionfaces on each of said extensions being a fraction o1"? the total circumference of said means to repeatedly set free said transmitting element, a release element, having like extensions and like frictiont'aces thereon, spring means pressing said release element against said transmitting element and in engagement with said frictiont'aces. a strain receiving member, an engaging element forming part oi? said receiving member. means toengage said release element with said engaging element, said release element to permanently disengage from said receiving member after a movement of said transmitting element in either one of two directions and in advance of said release element, the length of said movement being equal to the total length of said. friction faces and means to return into enga ement the frictionfaces of both of. said elements.

20. In mechanism of the character described. a strain inducing member, ronnd strain transmitting element, a plurality of extensions on said element, each of said extensions having one or more angular trictionfaces, the total length of said trictionfaces on each of said extensions being a fraction of the total circnmterence oi" said transmitting element, a release element. having like extensions and like friction faces thereon, spring means, pressing said release element against said transmitting element and in engagement with said trictiontaces, a strain receiving member, means to engage said release element with said receiving member, said release member to permanently disengage from said receiving memher after a movement of said transmitting element in either one of two directions and in advance oi said release element, the length of said movementbeing equal to the total length of said friction faces and means to return into engagement the tri'ction faces of both or. said elements.

21. In mechanism oi the character described, 21 strain inducing member, a round strain transmitting element, a pliu'alitv oi extensions on said element, 'l rictiontaces on said extensions, the length of said frictionfaces on each of said extensions. beir traction of the total circumference oi said transmitting element, a release element having like extensions and trictiontaces thereon, sprin means, pressing said release'element against said transmitting element and in engagement with said irictiontaces. a strain receiving member, means to engage said release element with said receiving member. said release element to perm nently disengage from said receiving memher after a movement of said transmittinc: element in either one of two directions and in advance of said release element, the length or" said movement being equal to the length of said friction faces and means to return into engagement the friction faces of both of said elements.

2 In mechanism or". the charact (lescribed a strain inducing member, a round strain transmitting element, a plurality of extensions on said element, trictioni aces on said extensions, the length of said frictionfaces on each of said extensions being a fraction of the total circumference of said transmit-ting element, a release element hav ing like extensions and frictiontaces there on, pressure means, pressing said release element against said transmitting element and in engagement with said trictiontaces, a strain receiving member, means to engage said release elementwith said receiving member, said release element to permanently disengage from said receiving member after a movement of said transmitting element in either one of two directions and in advance of said release element, the length or" said movement being equal to the length of said trictionfaces and means to return into engagement the frictiontaces of both of said elements.

23. In mechanism of the character de scribed a strain inducing member, a strain transmitting element, a plurality of extensions 011 said element, each of said extensions having one or more angular trictionfaces, a release element having like extensions and like frictiontaces thereon, spring means pressing said release element against said trans mltting element and in engagement with said frictionfaces, a strain receiving member, an engaging element forming part of said receiving member, means to engage said release element with said engaging element, said release element to permanently disengage from said receiving member after movement of said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the frictiontaces of both oi said elements.

24-. In mechanism of the character described a strain inducing member, a strain transmitt ng element,'a plurality 0"" eaten sions of said element, each of said. extensions having one or more angular tri iiontaces, a release element having like extensions and like trictiont'aces thereon, pressure means pressing Said release element against transmitting element and in engagement with said frictiontaces, a strain receiving member, an engaging element forming part of said re ceiving member, means to engage said release element with said engaging element, said release element to permanently disengage from said receiving member after a move ment of said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the trictionfaces 0' both of said elements.

25. In mechanism of the character described a strain inducing member, a strain transmitting element, plurality enta il (l c to permanently disengage from sions on said element each of said extensions having one. or more angular ii'rictiontacess, a release element having like extensions and like trictioni'aces thereon, pressure means pressing, said release element against said transmitting element and in engagement with said trictionfaces, a strain receiving member means to engage said release memher. with said receiving member said release element to permanently disengage from said receiving member after a movement oi? said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the frictionfaces of both of said elements.

26. Inmechanism of the character described a strain inducing member, a st iin transmitting element, a plurality of extensions on said element trictiontaces on said extensions, a release element having like extensions and trictionfaces thereon, spring means pressing said release element against said transmitting element and in engagement with said friction'faces a strain receiving member, an engaging element, forming part of said receiving member, means to engage said release element with said engaging element, said release element to permanently disengage from saidreceiving member after a movement of said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the frictionfaces of both of said elements.

27. In mechanism of the character described a strain inducing member, a strain transmittingelement, a plurality of extensions on said element frictionfaces on said extensions, a release element having like extensions and frictiontaces thereon, pressure means, pressing said release element against said transmitting element and in engagement with said frictionfaces, a strain receiving member, an engaging element forming part of said receiving member,

- means to engage said release member with said engaging element, said release element said receiving member after a movement of said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the trictionfaces of both of said elements,

28. In mechanism of the character described a strain inducing member, a strain element in either one of two directions and in advance of said release element and means to return into engagement the triotionfaces of both of said elements.

29. In mechanismof the character described a strain inducing member, a strain transmitting element, angular trictionfaces thereon, a release element with like trictionfaces, pressure means, pressing said release element against said transmitting element and in engagement with said frictionfaces, a strain receiving member, means to engage said release element with said receiving member, said. release element to permanently disengage from said receiving member after a movement of said transmitting element in either one of two directions. and in advance of said release element and means to return into engagementthe frictionfaces of both of said elements. 7

30. In mechanism of the character described a strain inducing member a strain transmitting element, frictionttaces thereon, a release element with like frictionfaces, spring means said release element against said transmitting element and in engagement with said trictionfaces, a strain receiving member engaging said release element means to permanently disengage said release element from said receiving member, if the transmitting power is in excess of the resisting power on said frictionfaces, said release element to disengage from said receiving member after a movement of said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the friction'faces of both of said elements.

gage said release element from said receiv ing member, if the transmitting power is in excess of the resisting power on said frictionfaces, said release element to disengage from said receiving member after a'movementof said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the frictiontaces of both of said elements.

32. In mechanism of the character described a strain inducing member, a strain transmitting element, friction'faces thereon, a release element with like frictionfaces, pressure means pressing said release element against said transmitting element and in engagement with said frictionfaces, a strain receiving member engaging said release element, means to permanently disengage said release element from said receiving member if the transmitting power is in excess of the resisting power on said friction faces, said release element to disengage from said receiving member after a movement of said transmitting element in either one of two directions and in advance of said release element and means to return into engagement the frictionfaces of both of said elements.

33. In mechanism of the character described, a strain inducing member, a strain transmitting element fast to said inducing member, a release element, friction faces on both said elements, pressure means to en gage the friction faces of said elements, a strain receiving member positively engaging said release element and means to positively release the latter from said receiving member, if the transmitting power is in excess of the resisting power on said friction faces.

34. In mechanism of the character described, a strain inducing member, a strain transmitting element fast to said inducing member, a release element, pressure means to engage under friction said transmitting and release elements, a strain receiving member positively engaging said release element and means to positively release the latter from said receiving member, if the transmitting power is in excess of the resisting friction power on said elements.

35. In mechanism of the character described, a strain inducing member, a strain receiving member, friction means for engagement of both said members, said friction means to positively release said engaged members, if the transmitting power is in excess of the resisting friction power.

Signed at New York city in the county of New York and State of New York this 20th day of May A. D. 1920.

ARTHUR PESTEL.

Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,449,054, ranted March 20, 1923, upon the application of Arthur Pest-el, of New York, N. 1., for an improvement in Strain-Releasing ldlechanism, errors appear in. the printed specification requiring correction as follows: Page 4, line 106, for the word lo read Two; page 5, strike out present lines (37 and 68, claim 1, and insert a strain rewiring member forming a. permanent part of said imZ acing member, a strain,- page 6, lines 100 and 110, claims 16 and 17, after the word and insert the Word means, page 7, line 111, claim 24, for the words of said element read on said element,

and line 115. after the word against insert the word said )a e 8 line 90 claim c l a: 7 a

30, after the word means insert the word pressing; same page, strike out present line 108, claim 31, and insert instead faces, spring means: pressing said release, and that the said Letters Patent should be read With these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of May, A. 1)., 1923.

[SEAL] KARL FENNING,

Acting Commissioner of Patents. 

